Testing flatness of the universe with probes of cosmic distances and growth

When using distance measurements to probe spatial curvature, the geometric degeneracy between curvature and dark energy in the distance-redshift relation typically requires either making strong assumptions about the dark energy evolution or sacrificing precision in a more model-independent approach. Measurements of the redshift evolution of the linear growth of perturbations can break the geometric degeneracy, providing curvature constraints that are both precise and model-independent. Future supernova, CMB, and cluster data have the potential to measure the curvature with an accuracy of sigma(Omega_K)=0.002, without specifying a particular dark energy phenomenology. In combination with distance measurements, the evolution of the growth function at low redshifts provides the strongest curvature constraint if the high-redshift universe is well approximated as being purely matter dominated. However, in the presence of early dark energy or massive neutrinos, the precision in curvature is reduced due to additional degeneracies, and precise normalization of the growth function relative to recombination is important for obtaining accurate constraints. Curvature limits from distances and growth compare favorably to other approaches to curvature estimation proposed in the literature, providing either greater accuracy or greater freedom from dark energy modeling assumptions, and are complementary due to the use of independent data sets. Model-independent estimates of curvature are critical for both testing inflation and obtaining unbiased constraints on dark energy parameters.Comment: 23 pages, 11 figures; submitted to Phys. Rev.

Business forms industry\u27s response to EDI and electronic substitutes

This project has two primary objectives. Both objectives will be achieved through research of current data and the creation, distribution and analysis of a business forms industry survey. The first objective was to draw attention to the growing demand for electronic substitutes for traditional printed business forms, and educate the business forms industry about the biggest threat and opportunity of these technologies, Electronic Data Interchange (EDI). This was accomplished by outlining the technology and processes of EDI and describing the various benefits of EDI over traditional printed business forms systems. Such educational descriptions and analysis were necessary due to the lack of attention given to the intense growth in electronic substitutes by business forms trade publications and leaders. The second objective was to quantify the level of awareness that exists for EDI throughout the business forms industry, assess the current and future investment in and development of EDI and electronic forms software and systems by the major forms producing companies of the U.S. and identify what level of leadership has been received with regards to combating or investing in these technologies. The answers to these questions represent new information not currently in existence. A survey of business forms producers was necessary to attain much of this information. The educational information predominantly focuses on EDI instead. of the complete range of electronic substitutes for business forms due to the significant effect that this one technology has. A wide range of sources were consulted, from business forms industry reports to EDI promoters to governmental commerce statistics. This extensive literature search confirmed my earliest convictions that there is a lack of leadership and of significant educational information, at least in accessible print, about the threats and opportunities of EDI and other electronic technologies. A survey of 155 randomly selected forms producers from a population of approximately 500, netted 40 respondents. Most respondents were small producers who had experienced increases in both sales and profits in the past year. The survey shows that forms producers claim to have a fair degree of knowledge about EDI, believe that EDI will have a significant affect on the business forms industry, and EDI offers a fair degree of advantage over the traditional business forms system. Most respondents do not, however, monitor their customers use of electronic substitues for business forms. Most respondents do not invest in electronic technologies as a product or service alternative to current business forms. When asked about their desired role in providing such technologies and future participation in an EDI VAN service project, most respondents were favorable to the ideas. When asked if the forms industry leadership had done enough to educate them about electronic technology threats and opportunities, respondents definitely felt neglected and desired more information. The comments respondents wrote on the surveys were interesting but showed a general lack of understanding for what investment in new technologies really entails. Surprisingly, despite the small size of most of the firms responding to the survey and the fact that most had experienced increased profits, most expressed their feelings that they had a good understanding of EDI, EDI had significant advantages over there products and services and they are interested in investing in new technonlogies. In general it is clear, but perhaps not definitively conclusive, that hypotheses 1 and 2 are false and hypotheses 3 and 4 are true. Further questions are probed and answered in the Conclusions section. This report is an excellent pilot study but must be expanded and refined in order to formulate concrete recommendations to aid the industry